In Genesis 10, immediately before the Tower of Babel narrative, the people’s of the earth are listed. The immediate decentans of Shem, Ham, and Japheth number 70 new families that will become 70 nations of sorts.
As the Jesus Storybook Bible puts it, when introducing Abraham: “God’s world was still full of tears. It was never meant to be like this. But God was getting ready to do something about it. He was going to make all the wrong things right, and he was going to do it though… a family.”
So the people of Israel are God’s special and exclusive people but finally with Jesus salvation is brought to the gentiles. No. The salvation of the gentiles is all over the Old Testament!
In Leviticus 23:33-44, the Lord describes the rituals that are to take place during the Feast of Booths, which is also called the Feast of Tabernacles or the end of harvest feast. A different number of bulls are sacrificed each day during the 7 days of the festival. They total 70. Why? They 70 sacrifices are for the gentile nations. Israel is mediating for them as priests before God. Even way back then, His family was instructed to stand between the unknowning rebelious pagan people and their creator. He never forgot them for a moment and even as he turned his back on them, he kept them in his thoughts as he grew up his plan to redeem them in history.
(HT to Bible Matrix, Michael Bull, p.117 for this idea.)